DK159224B

DK159224B - LOW PRESSURE MERCURY VOLUME STEAM DISCHARGE LAMP

Info

Publication number: DK159224B
Application number: DK493183A
Authority: DK
Inventors: Adolf Jacobus Van Der Meer; Andreas Rinkel
Original assignee: Ind Tech Verlichting Bv
Priority date: 1982-11-03
Filing date: 1983-10-27
Publication date: 1990-09-17
Also published as: DK493183D0; NL8204258A; DK159224C; DK493183A; EP0108443A1

Description

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DK 159224 BDK 159224 B

Opfindelsen angår en rørformet udladningsbeholder, ved hvis ender der er anbragt elektroder, og som er anbragt i en lysgennemtrængelig kappe af plast, hvis længde tilnærmelsesvis svarer til udladningsbeholderens 5 længde, idet der mellem kappen og udladningsbeholderens ydervæg er anbragt afstandsholdere til at holde kappen i afstand fra udladningsbeholderen. En sådan lampe er kendt fra GB patentskrift nr. 1.352.298.The invention relates to a tubular discharge container, at the ends of which electrodes are arranged and which are arranged in a light-permeable sheath of plastic, the length of which approximately corresponds to the length of the discharge container 5, spacers being arranged between the sheath and the outer wall of the discharge container to hold the sheath. from the discharge container. Such a lamp is known from GB Patent Specification No. 1,352,298.

I lavtrykskviksølvdampudladningslamper er omsætnin-10 gen af den tilførte elektriske energi til ultraviolet stråling optimal ved et kviksølvdamptryk, der under lam” _3 pens driftsbetingelser ikke afviger væsentligt fra 6*10 torr (ca. 1 Pa). Dette er et damptryk, der med flydende kviksølv er i ligevægt ved en temperatur på ca. 40°C.In low-pressure mercury vapor discharge lamps, the conversion of the supplied electrical energy into ultraviolet radiation is optimal at a mercury vapor pressure which, under the operating conditions of lambs, does not differ significantly from 6 * 10 torr (approx. 1 Pa). This is a vapor pressure that is in equilibrium with liquid mercury at a temperature of approx. 40 ° C.

15 Den temperatur, der findes i udladningsbeholderen, er hovedsageligt bestemt af den energi, der tilføres lampen, og af omgivelsernes temperatur. Når en lavtrykskviksølvdampudladningslampe bruges på steder, hvor omgivelsernes temperatur er lav, f.eks. i udendørs lamper, gadebelys-20 ningslamper og tilsvarende armaturer, falder kviksølvdamptrykket i udladningsbeholderen, og følgelig aftager omsætningens virkningsgrad. Lysudbyttet fra lampen påvirkes da i negativ retning.15 The temperature contained in the discharge vessel is mainly determined by the energy supplied to the lamp and by the ambient temperature. When a low-pressure mercury vapor discharge lamp is used in places where the ambient temperature is low, e.g. in outdoor lamps, street lighting lamps and similar luminaires, the mercury vapor pressure in the discharge vessel decreases, and consequently the efficiency of the reaction decreases. The light output from the lamp is then affected in a negative direction.

I henhold til det nævnte GB patentskrift er der uden 25 om udladningsbeholderen anbragt en kappe af lysgennemtrængelig plast, der tjener som isolerende kappe og dermed til at forhindre, at lampens lysudbytte aftager ved en lav temperatur for omgivelserne. I nærheden af enderne er der omkring udladningsbeholderen anbragt specielle 30 ringformede afstandsholdere (f.eks. af kautschuk), hvorpå kappen er anbragt. Desuden er der til understøtning af kappen i området mellem de to ender anbragt en yderligere ringformet afstandsholder omkring udladningsbeholderen. Mellem kappen og udladningsbeholderens yder-35 væg er der altså skabt et ringformet rum. Ved anvendelsen af løse ringformede afstandsholdere for kappen er anbringelsen eller udskiftningen af en lampe ret van-According to the said GB patent specification, a sheath of light-permeable plastic is arranged outside the discharge container, which serves as an insulating sheath and thus to prevent the light output of the lamp from decreasing at a low temperature for the surroundings. Near the ends, special annular spacers (for example of rubber) are arranged around the discharge container, on which the jacket is arranged. In addition, to support the jacket in the area between the two ends, an additional annular spacer is arranged around the discharge container. An annular space is thus created between the casing and the outer wall of the discharge container. When using loose annular spacers for the jacket, the placement or replacement of a lamp is quite difficult.

DK 159224BDK 159224B

2 skelig, specielt hvis lampen er anbragt højtliggende eller på et vanskeligt tilgængeligt sted, således som det f.eks. er tilfældet ved gadelygter. Desuden har tilstedeværelsen af en yderligere ringformet afstandsholder 5 mellem kappens ender en yderligere ulempe, fordi der under lampens drift ved den yderligere ring let opstår kondensation af kviksølv som følge af den lokale lave væg-temperatur, der er en følge af den forholdsvis kraftige varmebortførsel over den yderligere ring til kappens y-10 derside. Kondensationen af kviksølv viser sig i form af pletter og punkter, hvorved lampen får et uæstetisk udseende, og der desuden forårsages lystab.2 is difficult, especially if the lamp is placed high or in a difficult-to-reach place, such as e.g. is the case with street lights. In addition, the presence of a further annular spacer 5 between the ends of the jacket has a further disadvantage, because during the operation of the lamp at the additional ring easily condensation of mercury occurs due to the local low wall temperature, which is due to the relatively strong heat dissipation over the additional ring to the y-10 of the sheath. The condensation of mercury manifests itself in the form of spots and dots, giving the lamp an unaesthetic appearance and also causing light loss.

DE offentliggørelsesskrift nr. 2 725 178 omtaler en rørformet lavtrykskviksølvdampudladningslampe med en 15 cylindrisk transparent plastkappe, som fastholdes til lampens ydervægge ved hjælp af endedæksler. Endedækslerne har cylindriske vægpartier, der omslutter enderne af plastkappen ved hjælp af ribbeformede afstandsstykker.DE Publication No. 2,725,178 discloses a tubular low pressure mercury vapor discharge lamp having a cylindrical transparent plastic sheath which is secured to the outer walls of the lamp by means of end caps. The end caps have cylindrical wall portions that enclose the ends of the plastic sheath by means of rib-shaped spacers.

Ulemper ved denne konstruktion er, at der kræves spe-20 cielle endedæksler, og at afstanden mellem kappen og udladningsbeholderens ydervæg er meget lille, således at kappens temperatur risikerer at stige til et forholdsis højt niveau.Disadvantages of this construction are that special end caps are required and that the distance between the jacket and the outer wall of the discharge container is very small, so that the temperature of the jacket risks rising to a relatively high level.

Med opfindelsen tilsigtes tilvejebragt en lavtryks-The object of the invention is to provide a low-pressure

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kviksølvdampudladningslampe af den indledningsvis nævnte art, der er således udformet, at de nævnte ulemper ikke optræder. Til opnåelse heraf er lampen ifølge opfindelsen ejendommelig ved, at afstandsholderne er udformet som i kappens væg tilvejebragte fordybninger, der ligger 3 0 an mod udladningsbeholderens ydervæg.mercury vapor discharge lamp of the kind mentioned at the outset, designed in such a way that the said disadvantages do not occur. To achieve this, the lamp according to the invention is characterized in that the spacers are designed as depressions provided in the wall of the casing which abut against the outer wall of the discharge container.

I lampen ifølge opfindelsen er den cylindriske kappe udformet således, at den på enkel måde kan anbringes om den rørformede udladningsbeholder. Anvendelsen af løse elementer til anbringelse af kappen er undgået. Den 35 cylindriske kappe af plast (f.eks. polycarbonat) har en sådan form, at den over fordybningerne trykker mod udladningsbeholderens ydervæg. Derved er afstanden mellemIn the lamp according to the invention, the cylindrical casing is designed so that it can be placed around the tubular discharge container in a simple manner. The use of loose elements for placing the sheath is avoided. The 35-cylinder plastic sheath (eg polycarbonate) has such a shape that it presses against the outer wall of the discharge container over the recesses. Thereby, the distance between

DK 159224 BDK 159224 B

3 kappens inderside og udladningskolbens yderside tilnærmelsesvis konstant over hele kappens længde.3 the inside of the jacket and the outside of the discharge piston approximately constant over the entire length of the jacket.

Ifølge en udførelsesform for lavtrykskviksølvdampudladningslampen ifølge opfindelsen ligger fordybningerne 5 an mod udladningsbeholderens ydervæg udfor elektroderne.According to an embodiment of the low-pressure mercury vapor discharge lamp according to the invention, the recesses 5 abut against the outer wall of the discharge container in front of the electrodes.

Under lampens drift har udladningsbeholderens væg udfor elektroderne på grund af den kraftige varmestråling fra disse en forholdsvis høj temperatur, således at der ikke sker kondensation af kviksølv på udladningsbeholderens 10 indervæg.During the operation of the lamp, the wall of the discharge container in front of the electrodes has a relatively high temperature due to the strong heat radiation from these, so that no condensation of mercury occurs on the inner wall of the discharge container 10.

1 henhold til en videreudvikling af lavtrykskviksølvdampudladningslampen ifølge opfindelsen har kappen ved hver ende tre i omkredsretningen ensartet fordelte fordybninger. Ved denne foranstaltning opnås der en ro- i c tationssymmetrisk understøtning af kappen på udladningsbeholderen, og der sikres et anlæg af samtlige fordybninger mod udladningsbeholderen.1 according to a further development of the low-pressure mercury vapor discharge lamp according to the invention, the jacket at each end has three uniformly distributed depressions in the circumferential direction. With this measure, a rotationally symmetrical support of the jacket on the discharge container is obtained, and an abutment of all the recesses against the discharge container is ensured.

Kviksølvdampudladningslampen ifølge opfindelsen, der har en lysgennemtrængelig kappe af plast, anvendes for- 20 trinsvis i lamper, der befinder sig på et forholdsvis koldt sted f.eks. på lygtepæle til gadebelysning. Der findes ikke tætnende eller afsluttende afstandsholdere eller andre tætnende elementer. Det ringformede rum mellem kappen og udladningsbeholderen er altså frit tilgæn-25 geligt for den omgivende luft. Det har vist sig, at der herved under lampens drift hindres en stigning af temperaturen og dermed kviksølvtrykket i udladningsbeholderen til en for stor værdi, hvilket kunne medføre en nedsættelse af lysudbyttet.The mercury vapor discharge lamp according to the invention, which has a light-transmissive sheath of plastic, is preferably used in lamps which are located in a relatively cold place, e.g. on lampposts for street lighting. There are no sealing or closing spacers or other sealing elements. The annular space between the jacket and the discharge container is thus freely accessible to the ambient air. It has been found that this prevents an increase in the temperature and thus the mercury pressure in the discharge vessel to an excessive value during the operation of the lamp, which could lead to a reduction in the light output.

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44

Opfindelsen forklares nærmere i det følgende under henvisning til den skematiske tegning, hvorThe invention is explained in more detail in the following with reference to the schematic drawing, in which

Figur 1 viser en udførelsesform for en lavtrykskviksølvdampudladningslampe ifølge opfindelsen delvis set fra 5 siden og delvis i længdesnit, ogFigure 1 shows an embodiment of a low-pressure mercury vapor discharge lamp according to the invention partly seen from the side and partly in longitudinal section, and

Figur 2 et snit gennem lampen i fig. 1 efter linien II-II.Figure 2 is a section through the lamp in fig. 1 along the line II-II.

Den i figur 1 viste lampe har en rørformet udlad-1 q ningsbeholder 1 af glas, hvis indre væg er beklædt med et lysstoflag 2, der f.eks. består af calciumhalophosphat, der er aktiveret med Mn og Sb. Udladningsbeholderen 1 er fyldt med kviksølv og en inaktiv luftart f.eks. argon (3 torr, 400 Pa). Ved enderne af udladningsbeholderen 1 15 er der anbragt elektroder 3 og 4,mellem hvilke der under lampens drift opretholdes en udladning.The lamp shown in Figure 1 has a tubular discharge container 1 of glass, the inner wall of which is covered with a fluorescent layer 2, which e.g. consists of calcium halophosphate activated with Mn and Sb. The discharge container 1 is filled with mercury and an inert gas e.g. argon (3 torr, 400 Pa). At the ends of the discharge container 1 15, electrodes 3 and 4 are arranged, between which a discharge is maintained during the operation of the lamp.

Udladningsbeholderen 1 er anbragt i en cylindrisk lysgennemtrængelig kappe 5 af plast, fortrinsvis poly-carbonat. Denne plast er forholdsvis stærk og stiv og 20 udsættes næppe for bøjning. Længden af kappen 5 er tilnærmelsesvis lig med længden af den rørformede udladningsbeholder 1. I væggen af kappen 5 er der udfor elektroderne 3 og 4 tilvejebragt fordybninger, der tjener som afstandsholdere. Fordybningerne 6a, 6b og 6c (jvf.The discharge container 1 is arranged in a cylindrical light-permeable sheath 5 of plastic, preferably polycarbonate. This plastic is relatively strong and rigid and 20 is hardly subject to bending. The length of the jacket 5 is approximately equal to the length of the tubular discharge container 1. In the wall of the jacket 5, recesses are provided in front of the electrodes 3 and 4, which serve as spacers. The recesses 6a, 6b and 6c (cf.

25 fig. 2) ligger an mod ydervæggen af udladningsbeholderen 1 aksialt på højde med en glødetråd 4a.FIG. 2) abuts against the outer wall of the discharge container 1 axially at the level of a filament 4a.

Som vist i fig. 2. er fordybningerne 6a, 6b og 6c fordelt ligeligt i kappens omkredsretning. 1 det viste udførelseseksempel er fordybningerne tilnærmelsesvis 30 kegleformede. Fordybningerne kan dog også have en anden form og kan f.eks. være cylindriske eller kugleformede.As shown in FIG. 2. the depressions 6a, 6b and 6c are evenly distributed in the circumferential direction of the jacket. In the exemplary embodiment shown, the recesses are approximately 30 conical. However, the depressions can also have a different shape and can e.g. be cylindrical or spherical.

I en i praksis udført lampe ifølge opfindelsen var der i en lysgennemtrængelig kappe af polycarbonat anbragt en lavtrykskviksølvdampudladningslampe med en ef-35 fekt på 20 W. Udladningsbeholderen havde en længde på ca. 60 cm og en yderdiameter på ca. 26 mm. Den cylin-In a lamp according to the invention embodied in practice, a low-pressure mercury vapor discharge lamp with a power of 20 W was arranged in a light-transmissive sheath of polycarbonate. The discharge container had a length of approx. 60 cm and an outer diameter of approx. 26 mm. The cylindrical

Claims

15 PATENT REQUIREMENTS

A low-pressure mercury vapor discharge lamp having a tubular discharge vessel (1), at the ends of which are electrodes (3,4) and arranged in a light-permeable cylindrical plastic sheath (5), the length 20 of which is approximately equal to the length of the discharge vessel (1) , spacers are arranged between the casing (5) and the outer wall of the discharge container (1) to keep the casing (5) at a distance from the discharge container, characterized in that the spacers are in the form of depressions (6a, 6b, 6c provided in the wall of the casing). ) abutting the outer wall of the discharge container (1).

Low-pressure mercury vapor discharge lamp according to Claim 1, characterized in that the recesses 30 (6a, 6b, 6c) abut against the outer wall of the discharge vessel (1) in front of the electrodes (3,4).

Low-pressure mercury vapor discharge lamp according to Claim 1 or 2, characterized in that the jacket (5) has three recesses (6a, 6b, 6c) uniformly distributed in the circumferential direction at each end.